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    <title>Document</title>
    <script>
        // 一行打印五个星星
        // console.log('111111');
        // for( var i=1;i<=5;i++){
        // console.log('1');
        // }
        var str ='';
        for(i=1;i<=5;i++){
           str=str+'1';
           console.log(str);
        }
        alert(str);
    </script>
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